Pipe-threading machine.



W. T. JOHNSTON. PIPE THBEADING MACHINE. APPLicAnoN FILED OCT. I1. ms.

Patented July 3, 1917.

3 SHEETS-SHEET l mIm/II W. T. JOHNSTON.

PIPE THREADING MACHINE.

APPLICATION man OCT-11.1915.

3 SHEETS-SHEET 2.

7:4 lwnm W. T. JOHNSTON.

PIPE THREADING MACHINE.

APPLICATION FILED oer. I1. 1915.

Patented July 3, 1917.

3 SHEETS-SHEET 3.

WILLIAM T. JOHNSTON, OF NEWPORT, KENTUCKY.

PIPE-THREADING- MACHINE.

Specification of Letters Patent.

Patented July 3, 19317.

Application filed October 11, 1915. Serial No. 55,136.

To all whom it may concern:

Be it known that 1, WILLIAM T. JOHN STON, a citizen of the United States, and a.

resident of the city of Newport, in. the county of Campbell and State of Kentucky, have invented certain new and useful Improvements in Pipe-Threading Machines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

y invention relates to machines for cutting pipe threads, wherein the pipe is engaged interiorly by a clutching device in which is supported a shaft for journaling a revolving member carrying a proper cuttlng tool. It has as its object the providing of a clutching device of great effectiveness and simplicity, and generally the structural improvement of a thread cutter of this type.

These objects are accomplished, and Various other advantages gained, as will be indicated by that certain construction and arrangement of parts to be hereinafter specifically pointed out and claimed.

In the drawings,

Figure 1 is a central longitudinal section of the device mounted in a pipe, partly in elevation.

Fig. 2 is a side elevation of the cutting member, partly broken away to show the mechanism for mounting the thread cutting tool and the master thread follower or chasing block.

Fig. 3 is an end elevation of the clutch mechanism in a pipe.

Fig. 4 is an end elevation of the clutch adjusting tool.

Fig. 5 is a front elevation of the cutting member.

Fig. 6 is a detail of the cam device for throwing out the thread cutting tool and master thread follower or chasing block.

Fig. 7 is a central longitudinal section of a modification of the device adapted to be used for interior cutting, partly in elevation.

Fig. 8 is a top plan view of the sleeve member for supporting the cutting tools, showing the two arms for interior and exterior work.

Fig. 9 is an elevation of a modification .a sleeve 4.

showing another means of adjusting the eX- terior cutting tool on the spring controlled cutter holder sleeve.

Fig. 10 is a detail section showing a method of mounting various sizes of master thread members on the clutching member.

Fig. 11 is a longitudinal section of a modification of my device.

Fig. 12 is a top plan view of the housing and the tool holder therein.

Fig. 12 is a detail side elevation of the holderraising camfinger in place on the housing.

The adaptation of my new and useful hand thread cutter, as shown in the drawings, is designed for cutting a tapering thread 1 on a pipe 2. The pipe 2 may be al ready in place in a vise or in a wall or floor, and the hand cutter applied thereto as will be described. The shaft 3 which supports the cutting device is slidably mounted in This sleeve has at one end the the master threads 5 for controlling the movement of the cutter, as will be explained, these threads being cut to a taper (Fig. 1). The threads may be straight instead of tapered, as desired.

A clutch collar 6, of elliptical bearing surface 6 on the outside and cone shaped surface 6" on the inside, is mounted loosely on the sleeve or spindle 4, so as to seat on the cone shaped flange 6 on the sleeve. The far end of the sleeve is reversely screwthreaded at 7 and has screwed onto it at this point another clutch collar 8, similar to the collar 6, but reversely faced.

Mounted so as to slide on the middle portion of the sleeve .4 is a clutch sleeve 9, which carries at each end three pivoted clutch fingers or pins 1O, 10, 11, 11, which pins contact with the elliptical bearing surfaces of the collars and are adapted to be forced against the inner surface of the pipe 2. For this purpose, the sleeve 4 is slotted at the forward end at 12 (Fig. 1) so as to receive the wrench pin 13 on the tool 14 (Fig. 4). toward the inner end of the sleeve 4, which allows the fingers 10 and 11 to be retracted from both collars so that the clutching device can be inserted in the pipe, the shaft 3 of the cutter being removed. The friction The operator screws the collar 8:

of the fingers against the collar 8 will prevent its turning with the sleeve, and when the operator turns said sleeve by means of the tool mentioned, the collar 8 will be drawn forwardly by the reverse threads and will force outwardly the clutch fingers into tight engagement with the inner surface of the pipe. The thrust on the collar 6 is in a straight line with the stress on the clutch pins because of the cone shaped seat 6.

In view of the fact that the fingers are angularly disposed and contact with the curved surface of the collars, the clamping forces will be set at such an angle to each other that any thrust or pull on the sleeve will cause the fingers to be pushed more tightly against the pipe at one end or the other.

When the clutch is mounted in the pipe, the shaft 3 is inserted therein. Fixedly mounted on the outer end of this shaft is a member 15 held in place by a nut 16, and the screwthreads 17 are formed on the shaft for a purpose to be described.

Secured to this journal member at one side is a rod 18, which has a longitudinal feather 19 (Fig. 2), and is screw-threaded at 20 above the feather, whence itextends outwardly to be used as a turning handle. The cutter is mounted on this rod, and another rod 21 is screwed into the journal 15 outer end to be used as the other handle of the cutter.

A sleeve 22, having a key 23, is slidably mounted on the rod 18, and is pressed toward the shaft 3 by a spring 2 1 held on the rod 18, adjustably for tension, by a nut 25 on the threaded portion 20 of the rod as above noted. I

The sleeve 22 has an arm 26, which is bent upwardly at 27 to form a holder for the V- pointed cutting tool 28. This tool has one corner cut awayto form a bearing surface 29 for any desired set screw (not shown) which will screw into the holder member 27. This set screw is intended to hold frictionally, but not to lock the cutting tool, and its position for different sized pipe is controlled by a capstan screw 30, which screws into the of the holder and bears on the inner end of the tool.

Also extending from the sleeve 22 is an arm 31, which carries at its end the master thread follower block, or chasing block 32. This block lies in mesh with the master threads 5 on the sleeve -l, hitherto mentioned as having the clutch device mounted on it.

hlounted on the threads 17, above mentioned as being formed near the end of the rod 3, is a cam collar 32 having a handle 33 (Figs. 2' and 6). \Vhen the handle is turned dowmvardly," the cam collar will press upwardly on the arm 31 and raise the chasing or follower block out of mesh with the master threads. This will allow the rod sleeve 1 and the chasing block dropped into f mesh with the threads 5 by means of the cam collar 32. The cutting tool, having been first placed into the holder, is then adjusted for the size of pipe so as to make a slight cut into the pipe when advanced onto it, by means of the capstan 30, the set screw for holding the tool being loosened only for removing it from or raising it in the holder. The handles are then turned by the operator and the whole cutter advanced in spiral (and tapering motion as drawn and controlled by the chasing block.

A blunt pointed tool is preferably used for the first cut, to rough out thedesired thread, the cam then being employed to release the cutter for removal to insert the sharper cutting tool shown. A number of cuts are made to completely finish a thread, the cutter being slid back each time by means of the raising cam.

The entire device can be taken apart for convenient packing for shipment, by removing the journal 15 from the shaft 3, removing the handle 21 from the journal and sliding the sleeve'22 off of the rod 18.

There are various modifications of my device. whereby the new and useful pipe clutch and cutter tool holder may be employed to cut away sections of pipe such as boiler fiues inside of the head of the boiler, to cut different shaped threads, and more easily adjust the cutter tool retaining members. i

As shown in Figs. 7 and 8, the sleeve 22 may in addition to the arm 26, have another arm 34, which extends at right angles to the other arm. The sleeve will have in addition to the feather 19, another feather 35, whereby the sleeve may be slidably mounted on the rod 18 at an angle so as to extend the arm 34: into the interior of the pipe.

The. arm 34 will preferably have a square hole 36in it to receive the cutter 37, the same to be held in place by a set screw 38. The arm will also have a screw hole 39 for an adjusting capstan screw 40, the head of which bears against the shaft 3.

As so formed, the operation of the device for cutting off a section of pipe will be to change the position of the sleeve 22 as above explained, and adjust the capstan so as to bring the cutter 37 into contact with the pipe on the interior thereof. The capstan screw 40 may be adjusted from time to time to force the cutter more and more against the pipe, and by revolving the handles as above described for the exterior thread cutinner collar and operate ting the pipe will be easily and accurately severed. A shifting of the collar 32 will also serve to feed the tool into the pipe.

it were ever necessary to interiorly thread large pipe such as this device is particularly valuable in connection with, it would be readily possible to employa master thread follower as an extension of the arm 34. But it is not believed to be necessary to show this modification as it would have no particular usefulness.

If it is desired to cut threads of various sizes, the clutch sleeve flange 6 is formed with an outer cone shaped face 6 A variety of interiorly screwthreaded sleeves 41 are provided, the same being adapted to screw overthe master thread 5 on the clutch sleeve, and bear against the cone shaped surface at 6 These sleeves 41 will then have a master thread 42 of the desired pitch and taper.

The means above described for adjusting the exterior thread cutter tool 28 by means of a capstan 30 is very simple and inexpensive in construction. It is desired to construct a modification of more complication but of easier operation, for adjusting the position of this tool; Accordingly the sleeve 22 on the rod 18 has a sleeve 43 keyed onto it at 44. This sleeve 43 has an extending arm 45 which carries the exterior cutter tool 28, held by a set screw.46.

Mounted on the sleeve 22 above the keyed sleeve that holds the tool, is a fixed collar 47 which has a capstan screw retaining extension 48. In this extension is the capstan screw 49, which is revolved by means of the sliding pin 50. The screw bears on the keyed sleeve and by turning it the said sleeve will be caused to assume the desired position. No means are provided for raising the tool holding sleeve 43, because this operation may be easily done by hand, with the finer adjustinents accomplished in a downward direct1on.

In constructions for threading smaller pipe, it is readily possible to provide for the clutch and the sleeve or spindle 4 and the shaft of the cutting tool mounting in a reverse manner, thereby saving considerable bulk in the machine. The sleeve 4 having as its function the actuation of two clamping collars, may be solid and the shaft of the tool holder hollow so as to fit over it. Thus the stationary spindle having a master thread on it and providing a mounting for a reciprocating and rotating tool may be employed, and the tool holder supported in a sleeve which engages over and slides and rotates on the spindle.

In the modification shown in Figs. 11-- 12, this method of construction is adopted in order to save space. .The spindle 51 is solid, and has a thread 52 to engage the the clutch in the same manner. be made small.

out of the clutch at 53 and has the master thread 54,0n it. This extended portion is thicker than the clutch operating portion if a tapered thread must be taken care of.

The sleeve 55, wide at the inner end and narrow at the outer, is slid over the spindle. This sleeve has an extension 56 at one side for a handle or rod, and at the other has a hollow tubular extension 57 This extension is a housing for the cutter tool holder 58 which is set into the housing with its tool holding arm 59 extending out through a cutaway portion 60 of the housing. A web 61 on this arm is engaged by a screw 62 which slides in a slot 63 in a lug 64 of the housing. Thus the tool holder is held nonrotatably but reciprocatingly in the housing. This mounting means is the equivalent of a feather and key, and less expensive.

A cap 64 to receive a handle or rod is mounted over the open top of the housing, and a washer- 65 in the cap forms one bearing of a spring 66, which finds its other hearing in a recess in the upper end of the holder 58. The holder extends down through the housing and into the sleeve, and has the follower block 59 at its lower end.

The tool mounting is the same as in the structure first described, and the operation is the same throughout. The saving is in the size of the member inserted in the pipe, and the loss is that the spindle extends so far that it would have to be removed to fit an elbow to a partly formed thread on the p1 e.

The housing has a pivoted cam finger 67 mounted on it and positioned to contact with a pin 68 on the tool holder, said pin protruding through a slot 69 in the housing. By pulling over the cam finger, the holder and follower and tool will be lifted out of mesh so that the sleeve carrying the housing may be withdrawn from the spindle.

It is believed that the device with its various modifications is now fully described and its operation suficiently noted. It is not desired that the claims be limited by implication to specific structure because of the mention of various equivalents and modifications without the mention of all such modifications that would be possible, as it seems evident that without departing from the spirit of my invention as defined in the claims that various other changes could readily be made.

Having thus described my invention, what I'claim as new and desire to secure by Letters Patent, is

1. In combination with means for engaging a pipe interiorly, the same having)-. a master thread thereon, means for revolu ly mounting and guiding a thread cutter holder, and a thread cutter holder having members thereon for retaining cutter tools for exteriorly and interiorly cutting into the pipe, said exterior tool retaining member having a follower member connected thereto.

2. In combination with means for engaging a pipe interiorly, the same havingO a master thread thereon, means for revolu ly mounting and guiding a threaded cutter holder, and a thread cutter holder having members thereon for retaining cutter tools for exteriorly and interiorly cutting into the pipe, said thread cutter holder being adjustably mounted on its mounting means so as to be adaptable to use with either cutter tool retaining member, and said exterior tool retaining member having a follower member connected thereto.

3. In a device of the character described, the combination. with a clutch member to engage the inside of a pipe, a cutter tool holder supported thereby, means on the clutch member for removably mounting a master thread member, and a master thread follower and means for mounting the same on said tool holder.

4. In a device of the character described, a clutch member to engage the inside of a pipe, a cutter tool holder supported by said clutch, means on the clutch member for removably mounting a master thread member comprising a screw threaded member to removably receive a variety of forms of interiorly threaded master thread members, said holder having a master thread follower mounted thereon.

5. In a device of the character described, a clutch sleeve adapted to be insertedin a pipe, a tool holder having a shaft for slidably and revolubly engaging the clutch sleeve, pivoted fingers on the clutch, and collars on the clutch having curved surfaces to abut against the fingers whereby the direct pressure of the collars thereon is at an acute angle to the axis of the pipe, and means for bringing;

the collars together by revolving the sleeve to expand the fingers against the inner surface of the pipe.

6. In a device of the character described, a cylindrical clutch sleeve, means slidable thereon, having clutch fingers pivoted thereto, a fixed collar on said clutch sleeve positioned so as to contact with part of said fingers, and a collar threaded on said clutch sleeve and adapted to be moved by the rotation of the said member into-contact with the balance of said fingers, thereby sliding the other fingers against the fixed collar and a thread cutter having a shaft for sliding into said sleeve and a clutch for engaging the same, for the, purpose described.

7. In a device of the character described, in combination with a tubular clutch member having means thereon for clutching the interior of a pipe, a spindle slidable and rotatable in the tubular member, a master thread, a rod on the spindle, a cutter holder slidably mounted on the spindle, a master thread follower on the cutter holder, and a cam collar on'the spindle and adapted to contact with the holder, to raise it and the parts thereon out of operative position.

8. In a device of the character specified, the combination with a shaft suitably retained in a pipe clutching mechanism, a rod suitably journaled on said shaft, a sleeve slidable on said rod, and keyed against revolution thereon, a spring around said rod, a nut screwed on said rod and pressing the spring against the sleeve, and means on the sleeve for mounting a cutter tool and a master thread follower.

WILLIAM T; JOHNSTON. 

